U.S. patent application number 16/578745 was filed with the patent office on 2020-03-26 for start control device, start control method, and vehicle.
The applicant listed for this patent is HONDA MOTOR CO., LTD.. Invention is credited to Masaya AGATA, Shuji KAMATA.
Application Number | 20200094841 16/578745 |
Document ID | / |
Family ID | 69883938 |
Filed Date | 2020-03-26 |
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United States Patent
Application |
20200094841 |
Kind Code |
A1 |
AGATA; Masaya ; et
al. |
March 26, 2020 |
START CONTROL DEVICE, START CONTROL METHOD, AND VEHICLE
Abstract
A start control device is a start control device that controls
start of a vehicle including a clutch that is engaged by the
hydraulic pressure supplied from a hydraulic pressure supply source
and a start device that starts a vehicle driving source, and
includes: a hydraulic pressure control unit that controls so that
the hydraulic pressure supply source supplies the hydraulic
pressure to the clutch if a start condition for the vehicle is
satisfied; and a start device control unit that controls the start
device so that the rotation speed of the vehicle driving source
reaches the predetermined rotation speed after the clutch is
engaged.
Inventors: |
AGATA; Masaya; (WAKO-SHI,
JP) ; KAMATA; Shuji; (WAKO-SHI, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HONDA MOTOR CO., LTD. |
Tokyo |
|
JP |
|
|
Family ID: |
69883938 |
Appl. No.: |
16/578745 |
Filed: |
September 23, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16D 25/14 20130101;
B60W 10/02 20130101; B60W 30/192 20130101; F16D 2500/30415
20130101; F16D 2500/3111 20130101; B60W 10/04 20130101; F16D
2500/31426 20130101; F16D 48/08 20130101; F16D 2500/50883 20130101;
F16D 2500/3144 20130101; F16D 2500/50239 20130101; B60Y 2300/192
20130101; F16D 2500/106 20130101; F16D 2500/30406 20130101; F16D
2500/30816 20130101; F16D 2500/1026 20130101 |
International
Class: |
B60W 30/192 20060101
B60W030/192; F16D 48/02 20060101 F16D048/02; F16D 48/08 20060101
F16D048/08; B60W 10/04 20060101 B60W010/04; B60W 10/02 20060101
B60W010/02 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 26, 2018 |
JP |
2018-180777 |
Claims
1. A start control device configured to control start of a vehicle,
the vehicle including a clutch that is engaged by a hydraulic
pressure supplied from a hydraulic pressure supply source and a
start device that starts a vehicle driving source, the start
control device comprising: a hydraulic pressure control unit
configured to control in a manner that the hydraulic pressure
supply source supplies the hydraulic pressure to the clutch if a
start condition for the vehicle is satisfied; and a start device
control unit configured to control the start device in a manner
that a rotation speed of the vehicle driving source reaches a
predetermined rotation speed after the clutch is engaged.
2. The start control device according to claim 1, wherein the
predetermined rotation speed is a rotation speed at which it is
possible that a clutch slip occurs when the clutch is engaged.
3. The start control device according to claim 1, wherein a first
time corresponding to a time after a start command is input from
the start device control unit to the start device and before the
rotation speed of the vehicle driving source reaches the
predetermined rotation speed is shorter than a second time
corresponding to a time after supply of the hydraulic pressure from
the hydraulic pressure supply source to the clutch is started and
before the clutch is engaged.
4. The start control device according to claim 3, wherein the start
device control unit delays a timing that the start command is input
to the start device, by a predetermined time with respect to a
timing that the start condition for the vehicle is satisfied, the
predetermined time corresponding to a time obtained by subtracting
the first time from the second time.
5. The start control device according to claim 1, wherein the start
device control unit supplies the start command to the start device
after the clutch is engaged.
6. The start control device according to claim 1, wherein the
hydraulic pressure supply source is an accumulator configured to
accumulate the hydraulic pressure generated by an oil pump.
7. The start control device according to claim 1, wherein the start
device is an integrated starter generator configured to generate
power additionally.
8. The start control device according to claim 1, wherein the start
of the vehicle driving source is restart of the vehicle driving
source that is automatically stopped when a predetermined stop
condition is satisfied.
9. A vehicle comprising a start control device, the start control
device configured to control start of the vehicle, the vehicle
including a clutch that is engaged by a hydraulic pressure supplied
from a hydraulic pressure supply source and a start device that
starts a vehicle driving source, the start control device
comprising: a hydraulic pressure control unit configured to control
in a manner that the hydraulic pressure supply source supplies the
hydraulic pressure to the clutch if a start condition for the
vehicle is satisfied; and a start device control unit configured to
control the start device in a manner that a rotation speed of the
vehicle driving source reaches a predetermined rotation speed after
the clutch is engaged.
10. A start control method for controlling start of a vehicle, the
vehicle including a clutch that is engaged by a hydraulic pressure
supplied from a hydraulic pressure supply source and a start device
that starts a vehicle driving source, the start control method
comprising: a step of supplying the hydraulic pressure from the
hydraulic pressure supply source to the clutch if a start condition
for the vehicle is satisfied; and a step of controlling the start
device in a manner that a rotation speed of the vehicle driving
source reaches a predetermined rotation speed after the clutch is
engaged.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2018-180777 filed on
Sep. 26, 2018, the contents of which are incorporated herein by
reference.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a start control device, a
start control method, and a vehicle.
Description of the Related Art
[0003] For saving fuel, reducing exhaust emission, reducing noise,
and so on, a vehicle with a function of stopping an engine
automatically when a predetermined condition is satisfied has been
suggested. Such a function is called an idle stop function. For
example, in such a vehicle, the engine is stopped when the speed of
the vehicle is zero, an accelerator pedal is not operated, or a
braking pedal is operated. When the engine is restarted, for
example, the hydraulic pressure accumulated in an accumulator is
supplied to a clutch so that the clutch is engaged.
[0004] According to International Publication No. WO 2010/073765,
an electromagnetic open/close valve is opened before a vehicle
driving source is restarted, so that the hydraulic pressure
accumulated in an accumulator is supplied to a hydraulic servo. In
International Publication No. WO 2010/073765, the electromagnetic
open/close valve can be opened for sure when the vehicle driving
source is restarted.
SUMMARY OF THE INVENTION
[0005] However, in International Publication No. WO 2010/073765, a
clutch may be engaged with the vehicle driving source having too
high rotation speed. If the clutch is engaged with the vehicle
driving source having too high rotation speed, an engagement shock
may occur.
[0006] An object of the present invention is to provide a start
control device, a start control method, and a vehicle that enable a
quick start of a vehicle while suppressing a clutch engagement
shock.
[0007] A start control device according to one aspect of the
present invention is a start control device configured to control
start of a vehicle, the vehicle including a clutch that is engaged
by a hydraulic pressure supplied from a hydraulic pressure supply
source and a start device that starts a vehicle driving source, the
start control device including: a hydraulic pressure control unit
configured to control in a manner that the hydraulic pressure
supply source supplies the hydraulic pressure to the clutch if a
start condition for the vehicle is satisfied; and a start device
control unit configured to control the start device in a manner
that a rotation speed of the vehicle driving source reaches a
predetermined rotation speed after the clutch is engaged.
[0008] A vehicle according to another aspect of the present
invention includes the start control device as described above.
[0009] A start control method according to another aspect of the
present invention is a start control method for controlling start
of a vehicle, the vehicle including a clutch that is engaged by a
hydraulic pressure supplied from a hydraulic pressure supply source
and a start device that starts a vehicle driving source, the start
control method including: a step of supplying the hydraulic
pressure from the hydraulic pressure supply source to the clutch if
a start condition for the vehicle is satisfied; and a step of
controlling the start device in a manner that a rotation speed of
the vehicle driving source reaches a predetermined rotation speed
after the clutch is engaged.
[0010] According to the present invention, the start control
device, the start control method, and the vehicle that enable a
quick start of the vehicle while suppressing a clutch engagement
shock can be provided.
[0011] The above and other objects, features, and advantages of the
present invention will become more apparent from the following
description when taken in conjunction with the accompanying
drawings in which a preferred embodiment of the present invention
is shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a block diagram conceptually illustrating a
vehicle including a start control device according to one
embodiment;
[0013] FIG. 2 is a flowchart of an operation of the start control
device according to the embodiment; and
[0014] FIG. 3 is a time chart of one example of the operation of
the start control device according to the embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] A preferred embodiment of a start control device, a start
control method, and a vehicle according to the present invention is
described in detail with reference to the attached drawings.
[0016] [Embodiment]
[0017] A start control device, a start control method, and a
vehicle according to one embodiment are described with reference to
the drawings. FIG. 1 is a block diagram conceptually illustrating
the vehicle including the start control device according to the
present embodiment.
[0018] As illustrated in FIG. 1, a vehicle 10 includes a vehicle
driving source 12, a clutch 14, a transmission 16, wheels 18, a
start device 20, and a battery 22. The vehicle 10 further includes
an oil pump 24, a valve 25, an electromagnetic open/close valve 26,
and an accumulator (hydraulic pressure supply source) 28. The
vehicle 10 additionally includes a start control device 30
according to the present embodiment. Although the vehicle 10
includes other components than those above, they are not
illustrated.
[0019] In order to simplify the description, some components are
illustrated conceptually.
[0020] The vehicle driving source 12 is an engine, for example, but
is not limited thereto. The clutch 14 is provided between the
vehicle driving source 12 and the transmission 16. The driving
force of the vehicle driving source 12 can be transmitted to the
wheels 18 through the clutch 14 and the transmission 16. The
transmission 16 can be a continuously variable transmission (CVT),
for example, but is not limited thereto.
[0021] The start device 20 is coupled to a crank shaft (not shown)
in the vehicle driving source 12 through a motive power
transmission mechanism. The motive power transmission mechanism is
a belt, a pulley, or the like, but is not limited to these
examples. The start device 20 can start the vehicle driving source
12 and can also generate power. That is to say, the start device 20
includes a function as an electric motor that drives and rotates
the crank shaft and a function as a power generator that generates
electric power through driving and rotating by the crank shaft. The
start device 20 with such a structure is referred to as an
integrated starter generator. The start device 20 is connected to
the battery 22. The start device 20 can drive and rotate the crank
shaft using the electric power supplied from the battery 22. The
electric power generated by the start device 20 can be supplied to
the battery 22.
[0022] While the vehicle 10 is traveling, the oil pump 24 is
operated. As the oil pump 24 is operated, hydraulic pressure can be
generated. An oil passage 40 connected to the oil pump 24 can
communicate with an oil passage 42 through the valve 25. The oil
passage 42 is connected to the clutch 14. The engagement and
disengagement of the clutch 14 can be controlled by the hydraulic
pressure in the oil passage 42. The hydraulic pressure in the oil
passage 42 can be controlled by opening and closing the valve 25.
When the hydraulic pressure in the oil passage 42 has become a
threshold or more, the clutch 14 is engaged. On the other hand,
when the hydraulic pressure in the oil passage 42 has become less
than the threshold, the clutch 14 is disengaged. The oil passage 42
is connected to a branch oil passage (oil passage) 46 at a
connection point 44. The branch oil passage 46 is connected to an
oil passage 48 through the electromagnetic open/close valve 26. The
oil passage 48 is connected to the accumulator 28. The hydraulic
pressure generated by the oil pump 24 can be accumulated in the
accumulator 28 through the oil passage 40, the branch oil passage
46, and the oil passage 48. The hydraulic pressure accumulated in
the accumulator 28 can be supplied to the clutch 14 through the oil
passage 48, the branch oil passage 46, and the oil passage 42. The
valve 25 and the electromagnetic open/close valve 26 can be
controlled by a hydraulic pressure control unit 36, which is
described below. Note that one valve 25 among a plurality of valves
constituting a valve group (not shown) is illustrated in FIG.
1.
[0023] If current is not supplied to a solenoid (not shown) in the
electromagnetic open/close valve (electromagnetic valve device) 26,
that is, if the current supply to the solenoid is OFF, the
electromagnetic open/close valve 26 can operate as follows. That is
to say, the electromagnetic open/close valve 26 can operate such
that when the hydraulic pressure in the oil passage 46 is higher
than that in the oil passage 48, the hydraulic pressure equivalent
to that in the oil passage 46 is accumulated in the accumulator 28.
On the other hand, the electromagnetic open/close valve 26 can
operate so that when the hydraulic pressure in the oil passage 46
is lower than that in the oil passage 48, the hydraulic pressure
accumulated in the accumulator 28 is kept in the accumulator 28. If
current is supplied to the solenoid in the electromagnetic
open/close valve 26, that is, if the current supply to the solenoid
is ON, the electromagnetic open/close valve 26 can operate as
follows. That is to say, the electromagnetic open/close valve 26
can operate such that the hydraulic pressure accumulated in the
accumulator 28 is supplied to the clutch 14 through the oil passage
48, the branch oil passage 46, and the oil passage 42. The
electromagnetic open/close valve 26 that can function as above can
be configured by using a check valve (not shown) or the like as
appropriate, for example. The start control device 30 includes a
calculation unit 32 and a storage unit 34. The calculation unit 32
may include, for example, a central processing unit (CPU). The
storage unit 34 includes, for example, a nonvolatile memory and a
volatile memory (neither is shown). By the control of each unit on
the basis of programs stored in the storage unit 34, the start of
the vehicle 10 is controlled.
[0024] The calculation unit 32 includes a determination unit 35,
the hydraulic pressure control unit 36, and a start device control
unit 38. The determination unit 35, the hydraulic pressure control
unit 36, and the start device control unit 38 can be achieved when
the calculation unit 32 executes the programs stored in the storage
unit 34. The determination unit 35 determines whether a start
condition for the vehicle 10 has been satisfied. The start
condition for the vehicle 10 is that the speed of the vehicle 10 is
zero, a brake pedal (not shown) is not operated, or an accelerator
pedal (not shown) is operated, for example, but is not limited to
these examples. The hydraulic pressure control unit 36 controls
such that the hydraulic pressure is supplied from the accumulator
28 to the clutch 14 if the start condition for the vehicle 10 is
satisfied. The start device control unit 38 controls the start
device 20 such that the rotation speed of the vehicle driving
source 12 reaches a predetermined rotation speed Npd after the
clutch 14 is engaged. The predetermined rotation speed Npd is the
rotation speed at which clutch slip could occur in the engagement
of the clutch 14. The predetermined rotation speed Npd is about 500
rpm, for example, but is not limited to this value.
[0025] The time after a start command is input from the start
device control unit 38 to the start device 20 and before the
rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd, is defined as a first time T1.
The time after the supply of the hydraulic pressure from the
accumulator 28 to the clutch 14 is started and before the clutch 14
is engaged, is defined as a second time T2. The second time T2 is
about 250 ms, for example, but is not limited to this value. The
first time T1 is shorter than the second time T2. The start device
control unit 38 delays the timing to input the start command to the
start device 20, by a predetermined time Tpd, which corresponds to
the time obtained by subtracting the first time T1 from the second
time T2, with respect to a timing that the start condition for the
vehicle 10 is satisfied.
[0026] FIG. 2 is a flowchart of the operation of the start control
device according to the present embodiment. FIG. 2 shows the
operation when the vehicle 10 is started.
[0027] In step S1, the determination unit 35 determines whether the
start condition for the vehicle 10 is satisfied. As described
above, the start condition for the vehicle 10 is that the speed of
the vehicle 10 is zero, the brake pedal is not operated, or the
accelerator pedal is operated, for example, but is not limited to
these examples. If the start condition for the vehicle 10 is
satisfied (Yes in step S1), the process advances to step S2. If the
start condition for the vehicle 10 is not satisfied (No in step
S1), step S1 is repeated.
[0028] In step S2, the hydraulic pressure control unit 36 opens the
electromagnetic open/close valve 26. When the electromagnetic
open/close valve 26 is opened, the hydraulic pressure accumulated
in the accumulator 28 is supplied to the clutch 14 through the oil
passage 48, the branch oil passage 46, and the oil passage 42.
After that, the process advances to step S3.
[0029] In step S3, the start device control unit 38 determines
whether the predetermined time Tpd has passed after the start
condition for the vehicle 10 is satisfied. The predetermined time
Tpd is the time corresponding to the time obtained by subtracting
the first time T1 from the second time T2 as described above. For
example, the time obtained by adding a certain margin to the time
obtained by subtracting the first time T1 from the second time T2
may correspond to the predetermined time Tpd. As described above,
the first time T1 is the time after the start command is input from
the start device control unit 38 to the start device 20 and before
the rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd. Moreover, as described above, the
second time T2 is the time after the supply of the hydraulic
pressure from the accumulator 28 to the clutch 14 is started and
before the clutch 14 is engaged. If the predetermined time Tpd has
passed after the start condition for the vehicle 10 is satisfied
(Yes in step S3), the process advances to step S4. If the
predetermined time Tpd has not passed after the start condition for
the vehicle 10 is satisfied, step S3 is repeated.
[0030] In step S4, the start device control unit 38 inputs the
start command to the start device 20. For example, starting to
supply a target torque signal, which is a signal expressing a
target torque of the start device 20, from the start device control
unit 38 to the start device 20 may correspond to inputting of the
start command to the start device 20.
[0031] FIG. 3 is a time chart of one example of the operation of
the start control device according to the present embodiment. In
FIG. 3, a horizontal axis indicates time. FIG. 3 shows an example
in which an idle stop is performed.
[0032] FIG. 3 shows a brake signal. The brake signal is a signal
expressing whether the brake pedal is operated. While the user is
operating the brake pedal (not shown), the brake signal is at an H
level, for example. While the user is not operating the brake
pedal, the brake signal is at an L level, for example. The timing
that the brake signal changes from the H level to the L level, for
example, may correspond to the timing that the start condition for
the vehicle 10 is satisfied. Although the timing that the brake
signal changes from the H level to the L level is the timing that
the start condition for the vehicle 10 is satisfied in the
following explanation, the timing is not limited thereto.
[0033] FIG. 3 also shows a control state for an idle stop
mechanism, that is, an I/S control state. In "ENGRUN", the vehicle
driving source 12 is operated normally. In "I/S shift", the state
shifts from the state where the vehicle driving source 12 is
operated normally to the idle stop. In "currently I/S", the idle
stop is currently performed. In "ENGRUN shift", the state shifts
from the idle stop state to the state where the vehicle driving
source 12 is operated normally.
[0034] FIG. 3 also shows the rotation speed of the engine. The
rotation speed of the vehicle driving source 12 in the present
embodiment is shown by a solid line. The rotation speed of the
vehicle driving source 12 in a comparative example is shown by a
dashed line. FIG. 3 also shows time measuring by a timer. In FIG.
3, the time measuring by the timer is shown conceptually. FIG. 3
also shows the target torque signal. This target torque signal is
supplied from the start device control unit 38 to the start device
20. In the present embodiment, the target torque signal is shown by
a solid line. The target torque signal in the comparative example
is shown by a dashed line.
[0035] FIG. 3 also shows the state of the electromagnetic
open/close valve 26. The state "accumulate" shows a state in which
the hydraulic pressure is accumulated in the accumulator 28 as the
oil pump 24 is operated. The state "keep" shows a state in which
the hydraulic pressure accumulated in the accumulator 28 is kept.
The state "release" shows a state in which the hydraulic pressure
accumulated in the accumulator 28 is supplied to the oil passages
46, 42. The electromagnetic open/close valve 26 is closed in the
states "accumulate" and "keep", and is open in the state "release".
FIG. 3 also shows the hydraulic pressure in the accumulator 28,
that is, the accumulator hydraulic pressure. FIG. 3 also shows the
hydraulic pressure to be supplied to the clutch 14, that is, the
clutch hydraulic pressure.
[0036] At a timing t1, the state starts to shift from the state
where the vehicle driving source 12 is operated normally to the
idle stop. As the state shifts from the state where the vehicle
driving source 12 is operated normally to the idle stop, the
rotation speed of the vehicle driving source 12 gradually
decreases.
[0037] At a timing t2, the rotation speed of the vehicle driving
source 12 becomes zero. When the rotation speed of the vehicle
driving source 12 has become zero, the oil pump 24 stops to drive,
and the hydraulic pressure that is supplied to the clutch 14
decreases.
[0038] At a timing t3, the hydraulic pressure that is supplied to
the clutch 14 becomes less than the threshold. If the hydraulic
pressure that is supplied to the clutch 14 becomes less than the
threshold, the clutch 14 is opened. Thus, the idling is
stopped.
[0039] At a timing t4, the hydraulic pressure that is supplied to
the clutch 14 becomes zero. The hydraulic pressure control unit 36
controls so as to close the valve 25 at a proper timing.
[0040] At a timing t5, the start condition for the vehicle 10 is
satisfied. When the start condition for the vehicle 10 has been
satisfied, the hydraulic pressure control unit 36 controls so as to
open the electromagnetic open/close valve 26. Thus, the hydraulic
pressure accumulated in the accumulator 28 is supplied to the
clutch 14 through the oil passage 48, the branch oil passage 46,
and the oil passage 42. Since the hydraulic pressure is supplied to
the branch oil passage 46 and the oil passage 42 through the oil
passage 48, the hydraulic pressure in the accumulator 28 decreases
gradually. On the other hand, since the hydraulic pressure
accumulated in the accumulator 28 is supplied to the oil passage
42, the hydraulic pressure that is supplied to the clutch 14
increases gradually. At a timing t7, the timer starts to measure
the time.
[0041] At a timing t6, the timer finishes measuring the time. The
time from the timing t5 to the timing t6 corresponds to the
predetermined time Tpd. At the timing t6, the start device control
unit 38 inputs the start command to the start device 20.
Specifically, the target torque signal is supplied from the start
device control unit 38 to the start device 20. Thus, the start
device 20 starts and at the timing t7, the vehicle driving source
12 starts to rotate.
[0042] At a timing t8, the hydraulic pressure that is supplied to
the clutch 14 becomes the threshold or more. When the hydraulic
pressure that is supplied to the clutch 14 has become the threshold
or more, the clutch 14 is engaged. The clutch 14 is engaged before
the rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd. Since the clutch 14 is engaged
before the rotation speed of the vehicle driving source 12 reaches
the predetermined rotation speed Npd, the engagement shock can be
suppressed. The time from the timing t5 to the timing t8
corresponds to the second time T2. Once the clutch 14 is engaged,
the vehicle 10 starts to travel and the oil pump 24 starts to
operate. The hydraulic pressure control unit 36 controls so as to
open the valve 25. Thus, the hydraulic pressure in the accumulator
28 and the hydraulic pressure in the clutch 14 increase
gradually.
[0043] At a timing t9, the rotation speed of the vehicle driving
source 12 reaches the predetermined rotation speed Npd. The time
from the timing t6 to the timing t9 corresponds to the first time
T1. From the viewpoint of the drivability, the time after the start
condition for the vehicle 10 is satisfied and before the rotation
speed of the vehicle driving source 12 reaches the predetermined
rotation speed Npd is preferably within 400 ms.
[0044] Performance of the start device 20 is being improved in
order to start the vehicle 10 quickly. As the start device 20
achieves better performance, it takes shorter after the start
command is input from the start device control unit 38 to the start
device 20 and before the rotation speed of the vehicle driving
source 12 reaches the predetermined rotation speed Npd. In the
comparative example in which the time after the start condition for
the vehicle 10 is satisfied and before the start command is input
to the start device 20 is relatively short, the following occurs.
That is to say, before the timing t9 when the clutch 14 is engaged,
the rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd. If the rotation speed of the
vehicle driving source 12 reaches the predetermined rotation speed
Npd before the clutch 14 is engaged, the engagement shock may occur
when the clutch 14 is engaged. On the other hand, in the present
embodiment, the timing that the start command is input to the start
device 20 can be delayed by the predetermined time Tpd with respect
to the timing that the start condition for the vehicle 10 is
satisfied. The predetermined time Tpd is the time corresponding to
the time obtained by subtracting the first time T1 from the second
time T2 as described above. The first time T1 is, as described
above, the time after the start command is input from the start
device control unit 38 to the start device 20 and before the
rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd. The second time T2 is, as
described above, the time required after the supply of the
hydraulic pressure from the accumulator 28 to the clutch 14 is
started and before the clutch 14 is engaged. The timing that the
start command is input to the start device 20 is delayed by the
predetermined time Tpd with respect to the timing that the start
condition for the vehicle 10 is satisfied; therefore, in the
present embodiment, the clutch 14 is engaged before the rotation
speed of the vehicle driving source 12 reaches the predetermined
rotation speed Npd. Since the clutch 14 is engaged before the
rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd, the engagement shock can be
suppressed in the present embodiment. Thus, in the present
embodiment, even if the start device 20, in which the time after
the start command is input to the start device 20 and before the
rotation speed of the vehicle driving source 12 reaches the
predetermined rotation speed Npd is relatively short, is used, the
engagement shock of the clutch 14 can be suppressed. Thus,
according to the present embodiment, it is possible to provide the
start control device 30 that can start quickly the vehicle 10 while
suppressing the engagement shock of the clutch 14.
[0045] [Modified Embodiment]
[0046] The preferred embodiment of the present invention has been
described; however, the present invention is not limited to the
aforementioned embodiment and various modifications are possible
without departing from the gist of the present invention.
[0047] For example, the above embodiment describes the case in
which the vehicle driving source 12, which is automatically stopped
when the predetermined stop condition is satisfied, is restarted,
that is, the vehicle is restarted from the idle stop state;
however, the present invention is not limited to this example. The
present invention is also applicable when the vehicle 10, which has
been unused for a while, is started.
[0048] In the above embodiment, the start device 20 is coupled to
the crank shaft through the motive power transmission mechanism
such as a belt; however, the present invention is not limited to
this example. The start device 20 may be provided between the
vehicle driving source 12 and the clutch 14.
[0049] In the above embodiment, the hydraulic pressure accumulated
in the accumulator 28 is supplied to the clutch 14, so that the
clutch 14 is engaged; however, the present invention is not limited
to this example. The hydraulic pressure may be supplied to the
clutch 14 by driving the oil pump 24, so that the clutch 14 is
engaged. The oil pump 24 can function as the hydraulic pressure
supply source that supplies the hydraulic pressure to the clutch
14.
[0050] In the above embodiment, the start device control unit 38
supplies the start command to the start device 20 after the
predetermined period Tpd; however, the present invention is not
limited to this example. The start control device 30 may supply the
start command to the start device 20 after the clutch 14 is
engaged. Whether the clutch 14 is engaged can be determined by, for
example, the determination unit 35. The determination unit 35 can
determine whether the clutch 14 is engaged on the basis of the
hydraulic pressure that is supplied to the clutch 14, for example.
The hydraulic pressure that is supplied to the clutch 14 can be
detected using a hydraulic sensor or the like (not shown), for
example. The hydraulic sensor is, for example, connectable to the
oil passage 42 or the like. For example, if the hydraulic pressure
that is supplied to the clutch 14 is more than or equal to the
threshold, the determination unit 35 may determine that the clutch
14 is engaged. On the other hand, if the hydraulic pressure that is
supplied to the clutch 14 is less than the threshold, the
determination unit 35 may determine that the clutch 14 is not
engaged. Even in this case, the rotation speed of the vehicle
driving source 12 can reach the predetermined rotation speed Npd
after the clutch 14 is engaged. Therefore, the start command may be
supplied to the start device 20 after the clutch 14 is engaged.
[0051] The summary of the embodiment is described below.
[0052] The start control device (30) is the start control device
configured to control the start of the vehicle (10), the vehicle
(10) including the clutch (14) that is engaged by the hydraulic
pressure supplied from the hydraulic pressure supply source (28)
and the start device (20) that starts the vehicle driving source
(12), and the start control device (30) includes: the hydraulic
pressure control unit (36) configured to control in a manner that
the hydraulic pressure supply source supplies the hydraulic
pressure to the clutch if the start condition for the vehicle is
satisfied; and the start device control unit (38) configured to
control the start device in a manner that the rotation speed of the
vehicle driving source reaches the predetermined rotation speed
(Npd) after the clutch is engaged. In this structure, since the
clutch is engaged before the rotation speed of the vehicle driving
source reaches the predetermined rotation speed, the engagement
shock can be suppressed.
[0053] The predetermined rotation speed may be the rotation speed
at which it is possible that the clutch slip occurs when the clutch
is engaged.
[0054] The first time (T1) corresponding to the time after the
start command is input from the start device control unit to the
start device and before the rotation speed of the vehicle driving
source reaches the predetermined rotation speed may be shorter than
the second time (T2) corresponding to the time after the supply of
the hydraulic pressure from the hydraulic pressure supply source to
the clutch is started and before the clutch is engaged. In this
structure, since the time after the start command is input from the
start device control unit to the start device and before the
rotation speed of the vehicle driving source reaches the
predetermined rotation speed is relatively short, the vehicle can
be started quickly.
[0055] The start device control unit may delay the timing (t6) that
the start command is input to the start device by the predetermined
time (Tpd) with respect to the timing (t5) that the start condition
for the vehicle is satisfied, the predetermined time (Tpd)
corresponding to the time obtained by subtracting the first time
from the second time. In the structure described above, since the
clutch is engaged at the proper timing, the vehicle can be started
quickly while the engagement shock is suppressed.
[0056] The start device control unit may supply the start command
to the start device after the clutch is engaged. Even in this
structure, since the clutch is engaged before the rotation speed of
the vehicle driving source reaches the predetermined rotation
speed, the engagement shock can be suppressed.
[0057] The hydraulic pressure supply source may be the accumulator
configured to accumulate the hydraulic pressure generated by the
oil pump (24). In this structure, since the hydraulic pressure can
be supplied to the clutch quickly, the vehicle can be started
quickly.
[0058] The start device may be the integrated starter generator
configured to generate power additionally.
[0059] The start of the vehicle driving source may be the restart
of the vehicle driving source that is automatically stopped when
the predetermined stop condition is satisfied.
[0060] The vehicle (10) includes the start control device as
described above.
[0061] The start control method is the start control method for
controlling the start of the vehicle, the vehicle including the
clutch that is engaged by the hydraulic pressure supplied from the
hydraulic pressure supply source and the start device that starts
the vehicle driving source, and the start control method includes:
the step (S2) of supplying the hydraulic pressure from the
hydraulic pressure supply source to the clutch if the start
condition for the vehicle is satisfied; and the step (S3, S4) of
controlling the start device in a manner that the rotation speed of
the vehicle driving source reaches the predetermined rotation speed
after the clutch is engaged.
* * * * *